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Wounded skin cells exhibit a fascinating phenomenon: they emit electric spikes that resemble the signals previously thought to be exclusive to nerve cells. This surprising discovery sheds light on the intricate mechanisms of wound healing and suggests that skin cells communicate through electrical signals to orchestrate repair processes.
For over a century and a half, it has been established that injuries influence the electrical fields surrounding skin cells, as noted by Min Zhao, a cell biologist at the University of California, Davis. However, it was only recently revealed that skin cells can produce electrical spikes similar to nerve cells. This research, led by bioengineer Sun-Min Yu and engineering scientist Steve Granick at the University of Massachusetts Amherst, utilized human skin cells and dog kidney cells cultivated on electrode-embedded chips to analyze this electrical activity. Both cell types belong to the epithelial family, which serves as protective barriers and lines various organs.
In their experiments, the researchers applied lasers to some cells and subsequently measured alterations in electrical activity. They discovered that these pulses, generated by both skin and kidney cells, are influenced by the movement of calcium ions and display a voltage comparable to that of nerve cell signals. However, there is a significant difference in speed; while nerve impulses are rapid, lasting mere milliseconds, the electrical spikes from epithelial cells occur at a much slower pace, taking one to two seconds to develop.
Interestingly, the slow nature of these signals almost caused Yu to overlook them entirely. Adjustments to the detection software, initially set to identify the faster nerve cell pulses, allowed the team to capture these slower spikes, which lasted over five hours after the initial injury. This prolonged signaling may serve to alert neighboring cells, enabling them to expel damaged cells and initiate replication processes necessary for wound repair. This slower and more enduring form of communication aligns with the inherent differences between nerve and epithelial cells: nerve cells facilitate quick reactions, while epithelial cells engage in gradual healing processes over days to weeks.
Zhao emphasized that these electrical spikes enrich our comprehension of the temporal dimensions involved in wound healing. They also underscore the need to appreciate the role that electrical activity plays, often overshadowed by biochemical or mechanical interactions. “We need to change that idea,” Zhao asserted, advocating for a broader perspective on the complex and multifaceted nature of wound healing that incorporates both electrical and biochemical signaling.
Although the study was confined to examining electrical activity in two-dimensional cell layers, Yu expresses interest in extending this research to understand how epithelial cells communicate within three-dimensional structures and in relation to other cell types.
Source
www.sciencenews.org